Generally, in an outfitting line in which doors are assembled with vehicle bodies, the door is carried towards the vehicle body, which is being moved by a conveyor. Thereafter, the approaching door is aligned with the vehicle body. Subsequently, the door is coupled to a door hinge of the vehicle body using a bolt.
In this process, the door must be carried at a speed corresponding to the movement speed of the vehicle body, which is being moved by the conveyor. Simultaneously, the position of the door with respect to the vehicle body must be precisely set.
As such, it is not easy to assemble the door with the vehicle body. To set the precise position of the door with respect to the vehicle body and to conduct the bolt tightening process, highly skilled technique has been required.
Furthermore, because the door is too heavy for one worker to carry, a separate door installation apparatus is required. However, a conventional door installation apparatus has no function of moving at a speed corresponding to the movement speed of the vehicle body, which is being carried by the conveyor. Therefore, the worker must carry the door to the moving vehicle body using the door installation apparatus and couple the door to the vehicle body using a bolt after aligning the door with the door hinge of the vehicle body. During even this process, because the vehicle body is being continuously moved by the conveyor, there has been a problem in that the bolt coupling process is difficult.